Rutledge, a National Park Service ranger since 1976, has been stationed on Adams Key for 18 years, a 79-acre dot in the vastness of Biscayne Bay, inhabited by humans for 4,000 years.

Once home to the Cocolobo Club, built in 1916 by Carl Fisher as an exclusive resort, it is now home to only five people: Tom and Becky Rutledge and daughters Amelia, 9, and Meredith, 12; and ranger John Bittner, 33, who lives next door in a two-bedroom, one-bath bungalow on stilts, nearly identical to the larger house that the Rutledges rent for $500.

The key is so remote that it is its own voting precinct.

There's also a public dock, picnic tables and a half-mile nature trail for visitors, who number about 150 per month.

If the Rutledge family's life were a television show, it would be Little House on the Island, idyllic and wholesome in a way that hardly seems possible in a wired and harried world.

The girls have been homeschooled all of their lives, mostly because of logistics. Their science lessons are all around: sea turtle nests and the island's centuries-old shell middens. The bay's flora and fauna. Meteor showers and constellations, so much clearer than from the mainland.

They have had a pet praying mantis named Henrietta and have befriended a great white heron named Big Bird and his night heron sidekick, Night-Night, regular visitors to their dock.

Somehow, the girls manage to survive without a home computer and weekends at the mall. They regularly cook family meals - often fish they caught - and read from shelves lined with animal books and wildlife guides.

Television is limited to the networks and PBS, and not much of that, Becky said. Communication is by cell phone.

"This environment is good for kids," Becky said. "What an opportunity. How many kids get to live in the middle of the ocean? Kids sit in school all day and come home and have tons of homework, and there's no place for them to go play because the neighborhoods aren't safe."

"I knew we were raising them right when a couple of years ago, I said, "Meredith, what do you want for Christmas?' And she said, "A cast net and a fillet knife.' All right!" Tom said.

They go to town - Homestead and Florida City - several days a week for piano and dance lessons and often venture into Miami-Dade County for modeling jobs.

But the family's island idyll is drawing to a close. Tom, 54, faces mandatory retirement from the Parks Service at 57.

He and Becky, 52, have bought island property in the Charleston, S.C., area, near relatives. They're studying stilt-house plans and will soon start to build in a place of "roads and churches and Wal-Marts, so you don't even know you're on an island," Becky said.

Still, there are marshes and tidal creeks, so the girls anticipated the change with mixed feelings.

On the plus side: shrimping, crabbing and living within biking distance of their cousins.

The minuses: "I'll miss the easiness to get out and do something, like go out in a boat and go kayaking," Meredith said.

"I like being able to see all the (island's) animals, because in the city the only animals you get to see are pigeons or alley cats or stray dogs," Amelia said. "And the city smells bad."

But she looked forward to public school.

"I'm not saying I'm going to love it, but I just want to try it," Amelia said. "I love it here, but I love it there, too."